吸力摩擦角对非饱和土边坡安全系数影响的探讨

The discussion of the affection of suction friction angle on the slope stability factor

通过有限元法计算应力场分布,用极限平衡法计算安全系数,对一均质土边坡进行了安全系数的计算,比较了极限平衡法、有限元强度折减法和有限元结合极限平衡法得到的安全系数,分析了不同计算方法的差别。在有限元结合极限平衡法中引入吸力摩擦角,分析了吸力摩擦角对边坡稳定安全系数的影响。结论认为,有限元强度折减法中采用等效面积圆屈服准则的计算结果和本文中方法计算结果很吻合,验证了本文中采用的有限元结合极限平衡法的合理性;对不同的坡比,吸力摩擦角增大时安全系数呈平行的直线上升,滑坡方量呈阶段性的上升,最后趋于稳定。

The finite element method was used to ensure the tress distribution, as the limit equilibrium method was used to compute the safety factor. By this way, the safety factor of a homogenous soil slope was calculated, and the factors of limit equilibrium method, strength reduction FEM, the FEM within limit equilibrium method were compared. The suction friction angle was absorbed into the FEM within limit equilibrium method, analyzed the affection of suction friction angle on the slope＇s safety factor. At last, the conclusion was drawn as while the strength reduction FEM was used it should used equivalent area yield criterion. In addition, the reliability of the FEM within limit equilibrium method was proved. As the suction friction angle increasing, the safety factor straight climb, and the volume of sliding mass stage accend.